26                                 FISH OF BAY OF BENGAL           [Vol. XXVIII, Part 1,

per cent ethyl alcohol containing 0.2 mg. of CuSO₄ 5H₂O. The colour intensity of
the extracts was measured with a Klett-Summerson Photo-electric Colorimeter
using 550 mµ filter. Evaluation of the amounts was made from standard curves
obtained for individual amino acids using the identical methods for chromatographic
separation and elution.

For determination of leucine, isoleucine, histidine, methionine and cystine the same
procedure was followed with the exception that an unbuffered paper was used for the
chromatogram.

                         RESULTS AND DISCUSSION

Average values of amino-acid estimations of five samples of each variety of fish
are given on Table 1.

                                      TABLE I

Amino acid content in gm. of N₂ per 100 gm. of fat-free dried tissue

As tryptophane was destroyed during acid hydrolysis no figures for tryptophane
are given.

It will be observed that the muscle tissues of the three varieties of fish investi-
gated contain all the essential amino acids, except methionine which is absent in
the flesh of Bombay Dak. Hence, these varieties of fish may supply good protein
provided they are otherwise edible.

                                      SUMMARY

Amino acid compositions of the muscle tissues of three varieties of fish, i.e. Shark,
Ribbon and Bombay Dak, from Bay of Bengal, are reported. All of them are
found to be good sources of essential amino acids except methionine which is absent
in Bombay Dak muscle.

                                ACKNKOWLEDGMENT

Authors are thankful to Indian Council of Agricultural Research for financing a
scheme of which this investigation forms a part.

                                REFERENCES

Subramanian and Rao, (1955). J. Sci. Ind. Res. 14C, 56
Giri, Radhakrishnan and Baidynathan, (1952). Anal. Chem. 24, 1677